DDR3 made its debut in mid-2007 when Intel released P35 chipset with support for DDR3. Today nearly all desktop, mobile and server platforms support DDR3. iSuppli estimates that DDR3 will account for roughly 90% of DRAM sales this year. However, the next generation DRAM technology is already just around the corner and JEDEC is scheduled to release the full DDR4 specification next year. Yesterday, JEDEC published some of the specifications of the upcoming DDR4 technology.

First and foremost, DDR4 will concentrate on performance and power consumption. The latter is achieved by lowering the voltage to 1.2V, compared to DDR3's 1.5V (although there are DDR3 modules with lower or higher voltage but 1.5V is the standard for most). The performance gain is achieved by increasing the frequency and DDR4 will start from 1600MHz. It's likely that we will see 1866MHz or 2133MHz modules as the standard though, considering that DDR3 went straight for 1066MHz as well, even though a 800MHz specification existed too. The projected maximum speed for DDR4 is 3200MHz but then again, DDR3's maximum is 1600MHz, yet 2133MHz DDR3 modules are available. We will likely see even higher bandwidth DDR4 modules in the future. JEDEC lists the prefetch buffer for DDR4 as 8n, which is identical to DDR3. If this ends up being the case the bulk of the performance increase will be due to higher operating frequencies enabled through more advanced signaling.

The higher operating frequencies come at the expense of some serialization of the interface. The SDRAM memory interface remains one of the last parallel buses in modern PCs. While it doesn't look like DDR4 will change that, we have heardreports of the new memory standard moving to a point-to-point protocol. In other words: one DDR4 module per memory channel. Note that JEDEC hasn't confirmed this will officially make it into the DDR4 spec.

We still need to see chipsets that support more than 1833 bus, keep in mind that even if you have 3200Mhz memory, if the APU itself cant go any higher than... let's say 2400, it will be mostly useless.

And sincerely, I dont se that happening soon, it's expensive to support such high buses and if AMD or intel wanted to do it, they could have done it by now with DDR3 at 2000-2133Mhz.Reply

Sooner or later faster buses will be supported. 2133MHz DDR3 didn't come out right after P35, it took years. The same will happen with DDR4. It will take a few years before we will see speeds close to the maximum.

We either need CPU to have Tri or Quad memory channel without all the MB space ( using Laptop DRAM as standard ? ) or we need a new type of Memory.

If every node shrink means doubling of Gfx Power, the life time of memory is suppose to last 2 to 3 node shrink. and if we count 1.5x the bandwidth for doubling the Gfx power, that means we need at least 3x memory bandwidth.

Quad Channel is something CPU maker dont want to go because of the wasted Die Space.

So are we stuck for the next few years starved by memory bandwidth?Reply

Memory bandwidth is not the bottleneck. dGPUs have their own VRAM which is often faster than regular RAM. Hence the need for RAM isn't that huge and tests show that faster RAM provides no better performance

the speed doesn't even make sense because most ddr3 that claims to hit 1866+ are not at 1.5V. What's the whole point if you have to crank it to 1.65V or higher? especially if you intend on populating all the slots.Reply